From 6fa94ac455819e37a16ed8439be4bbf0b869884c Mon Sep 17 00:00:00 2001 Message-Id: <6fa94ac455819e37a16ed8439be4bbf0b869884c.1387276076.git.minovotn@redhat.com> In-Reply-To: References: From: Vlad Yasevich Date: Wed, 11 Dec 2013 21:40:06 +0100 Subject: [PATCH 16/16] net: Update netdev peer on link change RH-Author: Vlad Yasevich Message-id: <1386798006-31753-1-git-send-email-vyasevic@redhat.com> Patchwork-id: 56241 O-Subject: [RHEL 7.0 qemu PATCH] net: Update netdev peer on link change Bugzilla: 1027571 RH-Acked-by: Amos Kong RH-Acked-by: Stefan Hajnoczi RH-Acked-by: Xiao Wang BZ: https://bugzilla.redhat.com/show_bug.cgi?id=1027571 Brew: http://brewweb.devel.redhat.com/brew/taskinfo?taskID=6714640 When a link change occurs on a backend (like tap), we currently do not propage such change to the nic. As a result, when someone turns off a link on a tap device, for instance, then a guest doesn't see that change and continues to try to send traffic or run DHCP even though the lower-layer is disconnected. This is OK when the network is set up as a HUB since the the guest may be connected to other HUB ports too, but when it's set up as a netdev, it makes thinkgs worse. The patch addresses this by setting the peers link down only when the peer is not a HUBPORT device. With this patch, in the following config -netdev tap,id=net0 -device e1000,mac=XXXXX,netdev=net0 when net0 link is turned off, the guest e1000 shows lower-layer link down. This allows guests to boot much faster in such configurations. With windows guest, it also allows the network to recover properly since windows will not configure the link-local IPv4 address, and when the link is turned on, the proper address address is configured. Signed-off-by: Vlad Yasevich Signed-off-by: Stefan Hajnoczi (cherry picked from commit 02d38fcb2caa4454cf4ed728d5908c3cc9ba47be) --- net/net.c | 26 +++++++++++++++++--------- 1 file changed, 17 insertions(+), 9 deletions(-) Signed-off-by: Michal Novotny --- net/net.c | 26 +++++++++++++++++--------- 1 file changed, 17 insertions(+), 9 deletions(-) diff --git a/net/net.c b/net/net.c index c0d61bf..a8c49fc 100644 --- a/net/net.c +++ b/net/net.c @@ -1059,15 +1059,23 @@ void qmp_set_link(const char *name, bool up, Error **errp) nc->info->link_status_changed(nc); } - /* Notify peer. Don't update peer link status: this makes it possible to - * disconnect from host network without notifying the guest. - * FIXME: is disconnected link status change operation useful? - * - * Current behaviour is compatible with qemu vlans where there could be - * multiple clients that can still communicate with each other in - * disconnected mode. For now maintain this compatibility. */ - if (nc->peer && nc->peer->info->link_status_changed) { - nc->peer->info->link_status_changed(nc->peer); + if (nc->peer) { + /* Change peer link only if the peer is NIC and then notify peer. + * If the peer is a HUBPORT or a backend, we do not change the + * link status. + * + * This behavior is compatible with qemu vlans where there could be + * multiple clients that can still communicate with each other in + * disconnected mode. For now maintain this compatibility. + */ + if (nc->peer->info->type == NET_CLIENT_OPTIONS_KIND_NIC) { + for (i = 0; i < queues; i++) { + ncs[i]->peer->link_down = !up; + } + } + if (nc->peer->info->link_status_changed) { + nc->peer->info->link_status_changed(nc->peer); + } } } -- 1.7.11.7